Well let me start off first by saying that it is getting really cold here and it snowed a lot over the weekend and I have been having to drive over ice to get to work in my 350z. Today when I got off work I turned my Z on and it was fine nothing wrong. However after about 2 miles of driving the brake light pops up and won't go away. (I never use my parking brake so thats not it). I checked my parking brake, its off. I stomp on the pedal, nothing is wrong. I turned my car off and on its still there. What is wrong? I read in the owners manual if you have low brake fluid it will turn on when you brake or go excessive seeds. But this is STAYING on.

 

So, did you check the brake fluid level?

 

Eric, the light is there for a reason. As you have already checked to see that the hand brake lever is all the way down, the next thing to check is the brake fluid level in the master cylinder. Yes as the fluid drops to the point where the float just barely closes the light switch contacts the dash light will flick on with hard acceleration or hard braking. However, this is just the fluid sloshing up and down in the reservoir. With just a slight more fluid drop the light will stay on all the time.

If there are no obvious leaks, this is simply an indication of brake pads that at their wear limits. As the pads wear, the caliper pistons automatically self adjust inward, this requires fluid to flow from the master cylinder reservoir to the calipers. The light comes on to indicate a brake inspection is needed as the pads are now excessively worn.

 

Thanks for the reply Jennifer. Brake fluid seems ok, pads have quite a bit of wear but nothing that would seem to make it a problem.

Its worth noting about a month ago when it got cold my tire pressure light came on and I have made sure countless times all my tires are at 30-35 (changed countless times seeing what works nothing does). The light is still on.

Maybe these two problems go hand in hand and a sensor is broken?

 

are you sure that you have the sensors in the tires? for the brake, try topping it off.. it has a black rubber thing that sucks down when it is low... are you sure you are not seeing that

 

Well you have to go step by step to troubleshoot. Start by Inspecting the operation of the handbrake switch to be sure it’s not loose or malfunctioning. Also check down into the brake fluid reservoir to make sure the float is floating and not stuck down etc.

 

Forgot to reply. Thanks for the help, sensor wasn't working right it's all good now .